This invention relates to the preparation and use of phenolic age resistors for polymers, both unsaturated and saturated. More particularly, it concerns compounds comprised of a disubstituted phenolic group attached at the para position to a carbon chain containing sulfur, a carbonyl group, and a carboxylic ester moiety.
The use of sulfur-containing hindered phenols is known, e.g., see Canadian Pat. No. 904,339; U.S. Pat. Nos. Re. 27,004 and 3,590,083 and British Pat. No. 1,396,469.
The art disclosing hindered phenols is extensive, including those containing carbonyl or ester groups, see e.g., Japanese Pat. No. 27,735/68, U.S. Pat. No. 3,753,943; U.S. Pat. No. 3,810,929, Japanese Pat. No. 0468/63; Rubber Chemistry and Technology, Vol. 46, No. 1, Pp. 96-105, March, 1973; U.S. Pat. No. 3,714,122 and Canadian Pat. No. 812,262.